# paX: a power amplifier with error correction (2)

## The voltage amplifier and input buffer stages Last month we discussed the principle of error correction and developed an error-correction power output stage. In this installment we will use H.ec in a voltage amplification stage and present the complete amplifier. Products
Gerber file

Elektor recommends its business partner Eurocircuits as the company of choice for its own prototypes and volume production in selected cases. Component list

Resistors

(0.25W metal film)

R1-R4,R6,R8,R17,R18 = 47Ω

R7 = 220Ω

R9,R10,R12,R25,R34 = 4kΩ7

R11 = 249Ω

R13 = 2kΩ74

R16 = 5kΩ23

R19,R20,R30,R31 = 2kΩ15

R21-R24,R60 = 100Ω

R26,R27,R33,R40-R43,R46,R51 = 1kΩ

R28 = 10Ω

R29 = 3kΩ0

R32 = 33Ω

R35,R36 = 619Ω

R37,R38 = 680Ω

R39,R45 = 1MΩ

R44 = 7kΩ5

R47,R48 = 1kΩ8 2W MF

R49,R50 = 10 kΩ

R52-R55 = 0Ω22 5W ceramic

R64 = 1Ω5 2W

R65 = 6(8 2W

RV1, RV2 = 200( multiturn trimmer

R5,R14,R15,R56-R59, R61-R63 = not present

Capacitors

C1,C3,C23 = 150pF polypropylene

C2, C4,C5,C9,C14-C16,C19,C22, C24,C25 = 100nF cer.

C6-C8,C13,C21 = 1&#181;F 63V foil

C10 = 220nF 50V cer.

C11,C12,C17,C18 = 470&#181;F 63V

C26 = 1nF foil

Inductors

L1 = 5µH (see text)

Semiconductors

D1, D2, D5,D6,D10,D11 = zener diode 15V 0.5W

D3,D4,D9,D12,D13,D14 = 1N4148

D7,D8 = 1N4003

Q1,Q2,Q9 = 2SA1208

Q3,Q4,Q10 = 2SC2910

Q5,Q11,Q17,Q18 = BC546B

Q6,Q14,Q19,Q20 = BC556B

Q13,Q16 = STD03N (+ isolation pad &amp; mounting hardware)

Q12,Q15 = STD03P (+ isolation pad &amp; mounting hardware)

U3 = TL051CP

Miscellaneous

J9 = header 2 x 1 pin (signal input)

J10 = header 2 x 3 pin (+ flatcable)

4 IC sockets DIL08

PCB, ref. 071085-1